The invention relates to methods for generating and manipulating images, i.e., image processors, as well as products and the like either carrying the images and/or the coding therefor.
Examples of previously known systems and/or methods for generating images that transition from one to another are screen savers for computers, programs for generating so-called morphed images, etc. However, all of these systems/methods generate images in a sequence that are perceptibly different from one another, i.e., they generate images for the purpose of effecting a discernable transition over a relatively short period of time. The result is that two given sequential images are perceptibly different from each other. Thus, an ordinary human observer can perceive a difference between successive images or frames in the series.
At least one problem associated with the playback of a sequence of images with perceptible differences therebetween, is that the motion and/or flicker and flashing created by the transitions between images can be quite annoying, if not distracting. Many can relate to being distracted by the flashes caused by a nearby television, or simply nearby motion. Some might respond by redirecting their attention to the television or motion, even if only temporarily, due to the natural response to want to acquire information about the motion. Others might become agitated because of the constant bombardment of light signals on that person""s senses.
Relative to the use of the invention in image display, there are some issues worthy of consideration regarding electronic display devices. A display, such as a flat panel display, when mounted on a wall or the like, and when not in use, can present an invasive black space that can contrast with other aesthetic considerations such as art work located nearby or displaced by the display. Cathode ray tube devices, in contrast, have frequently been hidden within cabinets, but as they increase in size, they consume more space and become more difficult to conceal.
The invention provides methods/systems for producing images along a transition path (defined below) wherein sequential different images are imperceptibly different (defined below) from each other, media/devices carrying such images, and methods/systems employing such images. The result is the display of a series or set of images in such a way that an ordinary viewer will not perceive the transitions between different images, or motion caused by such transitions, except over relatively widely disparate points of time, and thus not be subject to the distractions/annoyance caused by changes in a display.
In one aspect, the resultant display of such an image series or set is a xe2x80x9cstillxe2x80x9d image that evolves unnoticeably over time, and perhaps even a type of art form. This then provides an image display that can allow a display to display images without introducing distraction. Further, such a display can present an aesthetic enhancement as an artistic outlet.
In an embodiment, the invention provides a method for generating images in which a series or set of transition images are generated along a transition path from a first image to a second image. The transition images are generated such that a given transition image is imperceptibly different from an immediately preceding image.
In an embodiment, the transition images are then displayed in sequence over a period of time sufficiently long so that a change in display from one image to a succeeding different image cannot be perceived by an ordinary human observer, yet over time, the display transitions from the first image to the second image.
In this application, for convenience, several definitions have been adopted and apply throughout. These definitions are as follows:
Transition path: a series or set of images representing a progression, an evolution or changes from a first image to a second image, in steps. Typically the progression will be rational, for example linear, exponential, etc, or otherwise reproducible. However, it is also contemplated that the progression can be random, and not reproducible. Further, typically, a series or set of images along the progression will be displayed chronologically, although other displays such as spatially displaced images, are contemplated. In the latter instance, a series of transition images can be displayed simultaneously but along some spatial continuum.
A series or set of images incorporating a transition path need not all be different, and indeed in at least one aspect of the invention, a series of images is provided in which each different image is provided as a set comprising a plurality of copies of the same image. This aspect is the result of current applications in which a series of images essentially comprises a movie upon playback, and current movie playback systems require that a plurality of copies of a given image be displayed in seriatim in order to achieve an effective slower timing between transitions between different images.
Further, a set of images can be formed which are imperceptibly different, yet which are not played back in the order generated. If the differences are sufficiently small, then some images may be displayed out of order of generation without being noticed.
The foregoing matters will become clearer below.
Transition image: an image along a transition path incorporating an image difference relative to a preceding image. The xe2x80x9csecond imagexe2x80x9d referred to in the definition of xe2x80x9ctransition pathxe2x80x9d can be a transition image, and typically is the last transition image along the transition path.
Image difference: any difference between two images, including differences in hue, brightness, saturation, color space component or angle of view, whether on a pixel level, subpixel level or block of pixels level.
Imperceptible image difference, images that are imperceptibly different, and the like: an image difference that cannot be perceived by an ordinary human observer. It is accepted that generally, an ordinary human observer cannot perceive a change of 20 percent or less in any single component of a color space. For example, an ordinary human observer typically cannot perceive a 20 percent change in any one of hue, luminance, saturation and a color component, such as cyan, magenta, yellow, red, or green. It has also been stated that an ordinary human observer cannot perceive a difference in motion below about 0.03 of a degree of the visual angle per second. A change in view of 5 seconds of arc of view or greater has also been deemed perceptible. Finally it has been stated that the threshold for the human eye is a function of the apparent angular size and brightness of the scene. In optimum conditions and spots greater than about 10 arc-minutes the contrast is as low as 0.3%, rising to about 1.0% at about 5 arc-minutes, 15% at about 1.0 arc-minute and about 30% at the smallest resolvable detail at about 0.7 arc-minute with normal eyesight. See Blackwell, H. R., Contrast Thresholds Of The Human Eye, J. Optical Society of America, Vol. 36, pp. 624-43 (1946).
In displaying images along a transition path, in which a given image is imperceptibly different from an immediately preceding different image, timing of the transition is also a consideration in maintaining imperceptibility. That is to say, presumably one could transition so fast through the series of images, that the transitions and/or motion displayed by such transitions would be noticeable, even though the difference between any two images in the series would be imperceptible. Accordingly, to transition imperceptibly through the different images, the timing of the display of each different image should be on the order of 5 seconds or more. Obviously, the longer the display period there is less chance for perception of the differences.
Accordingly, an aspect of the invention is a resultant display of images that appear as a still image, but which in reality progress through a sequence to provide an evolution in character and/or scene without perceptible motion or transitioning.
In an embodiment, of the invention, to generate a transition path, first and second images are compared, and then an imperceptibly different transition image is generated as an incremental change from the first image to the second image.
In an embodiment, the first and second images are processed in a digital format and are compared pixel by pixel, and a corresponding pixel is generated in a transition image that is twenty steps (pixel values) closer or less to the value of the corresponding pixel of the second image from value of the corresponding pixel of the first image.
These and other features and/or aspects of the invention are described below in the following detailed description of the presently preferred embodiments with reference to the accompanying drawings.